Wrong compiler warning

[Takashi Kato]

The following shouldn't warn unused variable of slot

(import (rnrs))

(cond ((assq 'a '((a . 1))) =>
       (lambda (slot) (cdr slot))))

[Takashi Kato]

The root cause of the warning is because of the lambda inlining.

[Takashi Kato]

Adding optmised flag on lvar to check if the variable is optimised out or really unused (Fixes #259)

→ <<cset 4ca89ec77f40>>